Gwinnett County police have made two more arrests and are planning to charge a third person in connection with a series of armored car robberies in metro Atlanta.  Authorities say at least one suspect is still at large.

In addition to Thursday's new arrests, DeKalb County police have charged at least three of the suspects in police custody with murder. The suspects facing murder charges in addition to armed robberies counts are Stacey Dooley, 27-year-old Ashley Henderson and 28-year-old Edward Thornton.

DeKalb County Police Spokeswoman, Mekka Parish, says authorities aren't releasing who pulled the trigger.  "At this point, our detectives are going to refrain from identifying who they believe the  actual shooter is.  I think the most important thing, especially for the family, is that all three are being charged with murder and aggravated assault," said Parish.

The two suspects charged Thursday were 27-year-old Ashley Henderson and 28-year-old Edward Thornton.  Henderson has been charged with three counts of conspiracy to commit armed robbery.  Police say Thornton's whereabouts are unknown at this time.

Detectives say one of the suspects facing charges is 32-year-old Veronica Bullard, a former employee at Dunbar Armored.  Police say she will be charged with at least one count of party to the crime of armed robbery.

Bullard, the former Dunbar Armored employee, is the sister-in-law to Quinton Booker, one of the suspects arrested Wednesday.

In addition to Booker, Stacey Dooley was arrested Wednesday in connection with at least three armored car robberies in metro Atlanta.  After executing a search warrant at Dooley's house, police recovered an AK-47.

The hunt for the suspects intensified after the murder of armored car guard Gary Castillo on March 15.

Castillo was making a pick up at the Kroger in the Toco Hills Shopping Center that morning when he was shot and killed.  The robber grabbed the bag of cash, hopped into a getaway car and sped off.

It was the latest in a string of armored car robberies in the metro area.  This series of eight armed robberies, which included the murder of the armed guard) began in the fall of 2010.  The heists occurred in Cobb, DeKalb and Gwinnett counties.